Shares in Dexia, the troubled Belgian-French bank, were suspended on Thursday amid continued uncertainty about whether France, Belgium – or both – were preparing to bail it out.

The board is to meet on Saturday in Paris to try to determine its fate after announcing that it was in talks about selling its Luxembourg arm, possibly to the duchy itself.

Belgian newspaper De Tijd reported that the government was preparing to nationalise the bank, which was bailed out in the early stages of the 2008 banking crisis with €6bn (£5bn) of cash – although local politicians made it clear that France needed to help carry the burden.

The shares will remain suspended until Monday, the bank said, after the Belgian regulators requested they were halted because more information was needed on the Luxembourg talks.

Finance minister Didier Reynders told reporters as he arrived for a government meeting: "We do not wish to end up holding the whole of Dexia Group. We need a solution that means we are not just financing the Belgian bank. We also need to finance the past. And we do not want to do that alone."

The cost of insuring Belgian government bonds against default has hit record levels since the government, along with that of France, made clear this week that it was standing behind the bank when its shares were in free-fall.

Belgian prime minister Yves Leterme, who is only a caretaker while the country struggles to form a government, also made clear that there needed to be "an equitable split of the costs".

A break up of Dexia is now regarded as inevitable, with a solution for Luxembourg likely first. "Dexia confirms having entered into exclusive negotiations with an international group of investors in which the state of Luxembourg will participate for the disposal of Dexia Banque Internationale à Luxembourg," the bank said.